The two-part tool assembly of the invention is intended primarily to overcome the limitation inherent in the prior art ratchet wrenches. This limitation occurs because the prior art ratchet wrenches exert a constant torque on the bolt being turned, and accordingly, when such a ratchet wrench is designed to exert sufficient torque initially to loosen a bolt, that torque persists when the bolt has been loosened and when it is not needed. This means that the prior art ratchet wrenches must be designed to incorporate more handle motion than is actually required for a particular operation, which is especially troublesome where space and/or accessibility are limited.
Unlike the prior art ratchet wrench, the tool of the present invention automatically matches the available torque with the torque required for a particular operation, this being achieved by varying the torque. This results in the particular operation being performed with a maximum speed for present torque requirements.
The two-part tool system of the invention in the embodiment to be described includes a squeeze wrench section and a ratchet wrench section which may be inserted into one another. When the two sections are used in combination, certain advantages are realized, including the following: (a) in the resulting ratchet wrench, the variable torque of the tool automatically matches the required stroke, and squeeze strokes can become longer as the turning of the bolt becomes easier so as to speed up the removal of the bolt; (b) the full stroke of the squeeze handle provides two-thirds to three-quarters of a turn to the bolt, which is advantageous over the prior art squeeze ratchet wrenches, and over the usual prior art swing-type ratchet wrenches, even for very accessible and exposed bolts, since the two-part tool system of the invention operates much faster than either type of the prior art ratchet wrenches; (c) the combined tool of the invention finds particular utility in the case of bolts for which the turning room is limited, and it operates to permit such bolts to be quickly and conveniently removed; (d) the combined tool of the invention also finds practical utility in the removal of bolts which are too loose to enable the usual ratchet wrench to be used because of the tendency of the bolt to turn on the back stroke, and yet which are too tight or inaccessible to permit hand removal, such bolts being quickly and easily removed by the combined tool of the invention. The combined tool also finds utility in the installation of nuts and bolts with dirty or damaged threads which requires a smooth, fast and highly controlled turning motion, and which requires that they be held squarely and firmly.
As mentioned above, the ratchet wrench section of the combined tool of the invention may be operated by itself and independently of the squeeze wrench section. When the ratchet wrench section is operated alone for removing bolts requiring low to moderately high torques, for example, a screwdriver-like tool can be inserted into the rear of the ratchet handle, allowing the bolt to be turned by the head of the ratchet handle where room to turn the handle itself is limited or nonexistent. The torque is multiplied about three times by the ratchet wrench section. A flexible cable drive may be used in conjunction with the ratchet wrench section to provide further remote access.
Likewise, the squeeze wrench section may be operated alone, for example, as a screwdriver or wrench. When so used, the squeeze wrench section provides variable torque automatically to match its turning ability with the turning requirements. The squeeze wrench section may be coupled to screwdriver bits to be used as a screwdriver, and when so used, the axial push into the screw can be controlled independently of the turning torque, which is especially useful when removing screws from worn holes. The squeeze wrench section uses a mechanism similar to the well-known "spiral ratchet screwdriver". However, as compared with the "spiral ratchet screwdriver", the squeeze wrench section of the invention enables looser screws to be turned more quickly with the squeezing motion than with the arm pushing motion of the "spiral ratchet screwdriver". Also, tighter screws can be withdrawn or inserted with a minimum of effort in the high torque part of the stroke of the squeeze wrench section of the invention. Also, controlled one-handed operation is possible with the squeeze wrench section.
It is, accordingly, an object of the present invention to provide an inexpensive two-part squeeze-ratchet wrench assembly which is light and easily portable, which is more compact than a power tool, and which is often as efficient, and which may be used in spaces which are inaccessible to usual air ratchet tools, and the like. The two-part tool of the invention operates with the same speed as air socket wrenches for the lower torques commonly encountered in turning bolts. The variable torque feature of the squeeze wrench section of the invention provides accurate control of the amount of bolt turns since smaller strokes allow increasingly smaller turn angles.